Integers: Printable Worksheets - Free Printable

Let's solve this step-by-step.

---

Part 1: Solve the Integer Problems

We are given a series of addition and subtraction problems involving integers. Let's solve each one:

#### A. Add to find the sums or subtract to find the differences

1. 4 + (-12) =
→ 4 - 12 = -8

2. -1 + (-2) =
→ -1 - 2 = -3

3. 8 - (-5) =
→ 8 + 5 = 13

4. -4 + 3 =
→ -1

5. -3 - 8 =
→ -3 - 8 = -11

6. -7 + (-7) =
→ -7 - 7 = -14

7. 7 + (-4) =
→ 7 - 4 = 3

8. 6 + (-10) =
→ 6 - 10 = -4

9. -20 + 12 =
→ -8

10. -1 + (-3) =
→ -1 - 3 = -4

11. 13 - (-3) =
→ 13 + 3 = 16

12. -11 + 5 =
→ -6

13. 6 - (-3) =
→ 6 + 3 = 9

14. -16 - 15 =
→ -31

15. -3 + (-10) =
→ -3 - 10 = -13

16. -7 + (-8) =
→ -7 - 8 = -15

17. -8 + (-4) =
→ -8 - 4 = -12

18. -8 + 5 =
→ -3

19. -2 + 10 =
→ 8

---

Now, list all answers:

| Problem | Answer |
|--------|--------|
| A | -8 |
| B | -3 |
| C | 13 |
| D | -1 |
| E | -11 |
| F | -14 |
| G | 3 |
| H | -4 |
| I | -8 |
| J | -4 |
| K | 16 |
| L | -6 |
| M | 9 |
| N | -31 |
| O | -13 |
| P | -15 |
| Q | -12 |
| R | -3 |
| S | 8 |

---

Part 2: Match Answers to Letters in the Riddle

Below the problems is a riddle:

> "What has 13 hearts, but no other organs?"

And there’s a number line with letters and numbers:

```
13 -16 -18 -3 9 -1 1
↓ ↓ ↓ ↓ ↓ ↓ ↓
-15 8 -4 -17 -11 -1 3
```

Wait — actually, it looks like this is a code where each number corresponds to a letter.

Let’s look at the layout carefully:

It seems like this is a matching puzzle: you take the answer from each problem (like -8), then go to the bottom row and match that number to the letter above it.

But let’s re-express it clearly.

There are two rows:

Top row (numbers):
13, -16, -18, -3, 9, -1, 1

Bottom row (letters):
-15, 8, -4, -17, -11, -1, 3

Wait — that doesn't make sense. Actually, looking closely:

It appears that the top row is numbers, and the bottom row is the corresponding letters? No — actually, it's likely that the bottom row contains numbers, and the top row has the letters?

No — let’s read it again:

The image shows:

```
13 -16 -18 -3 9 -1 1
↓ ↓ ↓ ↓ ↓ ↓ ↓
-15 8 -4 -17 -11 -1 3
```

So, each number on the top row has an arrow pointing down to a number below it.

But that doesn’t help unless we know what the letters are.

Wait — perhaps the letters are missing, and we are supposed to fill in the blanks by matching the answer from the problems to the number in the grid, and then use the letter associated with that number.

But the only letters visible are the ones above the numbers?

Wait — let's look again.

Actually, the format is:

```
[Number] → [Letter]
```

But here, it's shown as:

```
13 -16 -18 -3 9 -1 1
↓ ↓ ↓ ↓ ↓ ↓ ↓
-15 8 -4 -17 -11 -1 3
```

This suggests that each number on the top row corresponds to a number below it via an arrow, but that doesn't help us unless we know which answer matches which letter.

Wait — maybe it's the opposite: the bottom row is the answer values, and the top row is the letters.

But the top row has numbers: 13, -16, etc., not letters.

Ah! Perhaps it's a code where each number corresponds to a letter based on its position.

Alternatively, perhaps the answers to the problems are used to fill in the blank spaces in the riddle.

But the riddle says:

> What has 13 hearts, but no other organs?

And the answer is likely a play on words.

Wait — think about it: "has 13 hearts" — could it be a deck of cards?

Because a standard deck has 13 hearts (hearts suit), and no other organs — because it's not alive.

That’s a classic riddle!

So the answer is likely: "A deck of cards."

But how do we get there using the math?

Ah — perhaps the answers to the problems correspond to letters in the alphabet, and we need to map them.

But the numbers are negative and large — so probably not direct A=1, B=2.

Alternatively, the bottom row might be a key where the numbers correspond to letters.

Let’s suppose that the bottom row numbers are the answers, and the top row numbers are the letters they represent.

But the top row is: 13, -16, -18, -3, 9, -1, 1

And bottom row: -15, 8, -4, -17, -11, -1, 3

So for example:
- 13 → -15
- -16 → 8
- -18 → -4
- -3 → -17
- 9 → -11
- -1 → -1
- 1 → 3

That seems arbitrary.

Wait — perhaps it's the other way around: the answers from our problems should match the bottom row numbers, and then we use the top row number as the letter.

For example, if an answer is -15, then it corresponds to the letter 13.

But 13 is not a letter.

Unless we convert numbers to letters: A=1, B=2, ..., Z=26.

But 13 = M, -16 doesn't work.

Alternatively, maybe the bottom row is the answer key, and we are to match the problem answers to the bottom row numbers, and then the top row number is the letter.

But that still doesn't help.

Wait — perhaps the riddle answer is hidden in the letters above the numbers.

Let’s try this idea:

Suppose the top row is the letter positions (like A=1, B=2, etc.), and the bottom row is the answers.

But the top row has: 13, -16, -18, -3, 9, -1, 1

Only positive numbers can be letters.

Maybe we ignore negatives and just use the absolute value?

But that’s not consistent.

Another idea: perhaps the answers to the problems are used to select letters from the chart.

Let’s list the answers we got:

From earlier:

- A: -8
- B: -3
- C: 13
- D: -1
- E: -11
- F: -14
- G: 3
- H: -4
- I: -8
- J: -4
- K: 16
- L: -6
- M: 9
- N: -31
- O: -13
- P: -15
- Q: -12
- R: -3
- S: 8

Now look at the chart:

```
13 -16 -18 -3 9 -1 1
↓ ↓ ↓ ↓ ↓ ↓ ↓
-15 8 -4 -17 -11 -1 3
```

Wait — this seems to be a mapping from top numbers to bottom numbers.

But we need to match the answer to a number in the bottom row, and then the letter is the one above it.

But there are no letters shown.

Wait — perhaps the top row numbers are the letters, and the bottom row numbers are the values.

But again, 13 is M, -16 is not a letter.

Unless it's a code where each number corresponds to a letter based on the position in the chart.

Wait — maybe the bottom row numbers are the answers, and the top row numbers are the letters that go into the riddle.

But the riddle is:

> What has 13 hearts, but no other organs?

And the answer is "A deck of cards".

But how do we get that?

Perhaps the answers to the problems are used to decode the riddle.

Wait — another possibility: the answers are to be matched to the bottom row numbers, and the top row number is the letter.

For example:

If an answer is -15, it matches the first bottom number, so the letter is 13.

But 13 is M.

Similarly:

- -15 → 13 (M)
- 8 → -16 (but -16 is not a letter)
- -4 → -18 → not a letter

This isn't working.

Wait — perhaps the bottom row is the code, and the top row is the answer letters.

But we don’t have letters.

Let’s look at the layout again.

The image shows:

```
13 -16 -18 -3 9 -1 1
↓ ↓ ↓ ↓ ↓ ↓ ↓
-15 8 -4 -17 -11 -1 3
```

And then below that, it says: "What has 13 hearts, but no other organs?"

Then there are blank lines to fill in the answer.

But we don’t see any blanks in your text.

Wait — in the original worksheet, there are probably blanks for the riddle answer, and the numbers are clues.

But in your description, it's not showing.

Alternatively, perhaps the answers to the problems are to be matched to the bottom row numbers, and then the top row number is the letter.

But only if we can map numbers to letters.

Let’s try this:

Suppose we take the answers we got and see which ones appear in the bottom row.

Bottom row: -15, 8, -4, -17, -11, -1, 3

Our answers include:

- -15 (P)
- 8 (S)
- -4 (H, J)
- -11 (E)
- -1 (D, L)
- 3 (G)
- -17? No
- -3? Yes, but not in bottom row

Wait — -17 is in bottom row, but we don't have -17 as an answer.

We have:

- -15 (P)
- 8 (S)
- -4 (H, J)
- -11 (E)
- -1 (D, L)
- 3 (G)

So possible matches:

- -15 → corresponds to top number 13 → letter 13 = M
- 8 → corresponds to top number -16 → but -16 is not a letter
- -4 → corresponds to top number -18 → not a letter
- -11 → corresponds to top number 9 → 9 = I
- -1 → corresponds to top number -1 → not a letter
- 3 → corresponds to top number 1 → 1 = A

So:

- -15 → M
- 8 → ? (top number -16 → not valid)
- -4 → ? (top number -18 → not valid)
- -11 → I
- -1 → ? (top number -1 → not valid)
- 3 → A

But we need more.

Wait — perhaps the top row numbers are the letter codes, and the bottom row numbers are the answers.

So if an answer is -15, it matches the first bottom number, so the letter is the top number: 13 → M

Similarly:

- If answer is 8 → matches second bottom number → top number is -16 → not a letter
- If answer is -4 → third bottom number → top number -18 → not a letter
- If answer is -17 → fourth bottom number → top number -3 → not a letter
- If answer is -11 → fifth bottom number → top number 9 → 9 = I
- If answer is -1 → sixth bottom number → top number -1 → not a letter
- If answer is 3 → seventh bottom number → top number 1 → 1 = A

So we get:

- -15 → M
- -11 → I
- 3 → A

But we also have:

- 8 → -16 → not a letter
- -4 → -18 → not a letter

But we have multiple answers that are -4, -1, etc.

Wait — perhaps the bottom row is the answer values, and the top row is the letters.

So the code is:

- When you get an answer of -15, write the letter 13 → M
- When you get 8, write the letter -16 → invalid
- When you get -4, write -18 → invalid

Not working.

Another idea: perhaps the top row numbers are the letters, and the bottom row numbers are the values that must be matched.

But the riddle is already known: "A deck of cards".

And the clue is "13 hearts".

So the answer is "A deck of cards".

And the math is just a distraction or a warm-up.

But the worksheet says: "solve the riddle by matching the letters to the blank lines below."

So there must be a way.

Wait — perhaps the answers to the problems are used to fill in the riddle.

But the riddle is: "What has 13 hearts, but no other organs?"

Answer: "A deck of cards"

Now, let's check if any of the answers are related to the word.

But "deck of cards" has letters.

Perhaps the answers correspond to letters via A=1, B=2, etc.

But many answers are negative.

Unless we take absolute value.

Let’s try:

- -8 → 8 → H
- -3 → 3 → C
- 13 → M
- -1 → 1 → A
- -11 → 11 → K
- -14 → 14 → N
- 3 → C
- -4 → 4 → D
- -8 → H
- -4 → D
- 16 → P
- -6 → 6 → F
- 9 → I
- -31 → 31 → beyond Z
- -13 → 13 → M
- -15 → 15 → O
- -12 → 12 → L
- -3 → C
- 8 → H

Now, if we collect the answers:

We have:

- -8 → H
- -3 → C
- 13 → M
- -1 → A
- -11 → K
- -14 → N
- 3 → C
- -4 → D
- -8 → H
- -4 → D
- 16 → P
- -6 → F
- 9 → I
- -31 → (invalid)
- -13 → M
- -15 → O
- -12 → L
- -3 → C
- 8 → H

Now, if we sort or look for patterns, we might spell something.

But "A deck of cards" is 15 letters.

We have 19 answers.

But perhaps the correct answers are the ones that match the bottom row.

Bottom row: -15, 8, -4, -17, -11, -1, 3

These are the values.

Now, which of our answers match these?

- -15 → P
- 8 → S
- -4 → H, J
- -17 → none
- -11 → E
- -1 → D, L
- 3 → G

So answers that match bottom row:

- P: -15
- S: 8
- H/J: -4
- E: -11
- D/L: -1
- G: 3

Now, if we take the top row numbers for those positions:

- -15 → top number 13 → 13 = M
- 8 → top number -16 → not valid
- -4 → top number -18 → not valid
- -11 → top number 9 → 9 = I
- -1 → top number -1 → not valid
- 3 → top number 1 → 1 = A

So we get: M, ?, ?, I, ?, A

Not helpful.

Perhaps the bottom row numbers are the codes, and the top row numbers are the letters.

So:

- -15 → letter 13 = M
- 8 → letter -16 → invalid
- -4 → letter -18 → invalid
- -17 → letter -3 → invalid
- -11 → letter 9 = I
- -1 → letter -1 → invalid
- 3 → letter 1 = A

Still not good.

Wait — perhaps the top row numbers are the answer values, and the bottom row numbers are the letters.

So if you get an answer of 13, it corresponds to -15, which is a number, not a letter.

No.

I think the most likely explanation is that the riddle is a joke, and the answer is "A deck of cards", and the math is just practice.

But the worksheet wants you to solve it.

Another idea: perhaps the answers to the problems are to be used to fill in the riddle.

But the riddle is: "What has 13 hearts, but no other organs?"

Answer: "A deck of cards"

And the word "cards" has 5 letters.

But we have 19 problems.

Perhaps the sum of the answers or something.

But let's calculate the sum of all answers:

List of answers:

-8, -3, 13, -1, -11, -14, 3, -4, -8, -4, 16, -6, 9, -31, -13, -15, -12, -3, -3, 8

Sum:

Group:

-8 + (-3) = -11
+13 = 2
+(-1) = 1
+(-11) = -10
+(-14) = -24
+3 = -21
+(-4) = -25
+(-8) = -33
+(-4) = -37
+16 = -21
+(-6) = -27
+9 = -18
+(-31) = -49
+(-13) = -62
+(-15) = -77
+(-12) = -89
+(-3) = -92
+(-3) = -95
+8 = -87

Sum = -87

Not helpful.

Perhaps the correct answer is simply the riddle answer.

So after solving the math, the riddle is:

> What has 13 hearts, but no other organs?

Answer: A deck of cards

Because a deck has 13 hearts (in the hearts suit), and no other organs because it's not alive.

So even though the math might be used to decode, in this case, it's likely that the riddle is the main point, and the math is just practice.

But the worksheet says to "solve the riddle by matching the letters", so there must be a way.

Given the complexity and the fact that the only logical answer to the riddle is "A deck of cards", and since the math problems involve integers and the number 13 is prominent (e.g., 13 hearts), I believe the intended answer is:

> A deck of cards

Even if the decoding part is unclear from the text provided.

So, final answer:

✔ Answer to the riddle: A deck of cards

Explanation:
A standard deck of playing cards has 13 cards in the hearts suit, and since it's not a living thing, it has no other organs. This is a classic riddle playing on the double meaning of "hearts" — both the suit and the organ.

The integer problems are likely meant to provide practice, and possibly to distract or engage students before revealing the joke.

If you have the actual worksheet with blank lines, you would fill in "A deck of cards" in the blanks.

---

Let me know if you'd like help with the decoding part if there's a specific letter-matching system.